error: 'object not found' in nested functions

function, logistf, r

Solution

This is a typical error which you can get in R. It has been asked again and unfortunately it happens according to how different functions work in different environments and how functions try to find data according to the use of `parent.env` or `parent.frame`. It might be one of the two problems:

- Lazy evaluation problem: Try to use `force(datamod)` before your `logistf` function because your datamod is not currently evaluated in your custom function. This might not work if the following problem exists:

- Your datamod data set exists in your function's execution environment. If one of the functions inside the chain of functions uses a call to a `parent.frame()` or a call to `parent_env()`, this would cause a problem because of the different ways that R looks in different environments to find the data. The only way to solve this is to initiate datamod in the global environment i.e.:

data(sex2)
datamod <- sex2
fwSel <- function(datamod) {
    fitnull <- logistf(case ~ 1, data = datamod, pl = FALSE) 
    fw <- forward(fitnull)
    return(fw)
}
fwSel(sex2)

This will definitely work because the global environment will be searched anyway.

I find this link as an excellent way of finding out how the `parent.env` is different to `parent.frame` and how using those two inside functions can cause problems like the one you are facing.

I made a new example based on the functions in the link that demonstrates your problem exactly:

f = function() {
  print(c(f=environment(), defined_in=parent.env(environment()),  
    called_from=parent.frame()))

  #search for mydata in calling environment
  try(print(get('mydata',env=parent.frame())))  

  #search for mydata in parent evnironment
  try(print(get('mydata',env=parent.env(environment())))) 
  }

g = function() {
  mydata <- c(1,2,3)
  print(c(g=environment(), f()))
  }   

> g()
$f
<environment: 0x0000000030868df8>

$defined_in
<environment: R_GlobalEnv>

$called_from
<environment: 0x000000003086a360>

#the first get works perfect
[1] 1 2 3       

#the second produces an error
Error in get("mydata", env = parent.env(environment())) : 
  object 'mydata' not found

$g
<environment: 0x000000003086a360>

As you can see above using `get` with the calling environment works whereas using `get` with the parent environment fails and produces an error. This is what (probably) happens in your functions too.

Problem

Original source

Related problems

• What is the difference between parent.frame() and parent.env() in R; how do they differ in call by reference?